scholarly journals Microscopy simple or advance technique of material characterization

2019 ◽  
Vol 4 (1) ◽  
Author(s):  
Benard Odhiambo Obondo ◽  
Benard Oloo Nyangoye
Keyword(s):  
Optical Microscopy ◽  
Critical Role ◽  
Soft Materials ◽  
Optical Microscope ◽  
Advanced Materials ◽  
Materials Preparations ◽  
Dust Particles ◽  
Polished Surface ◽  
Accurate Information ◽  
Specimen Preparation

Optical microscopy with respect to advanced scientific research can be referred to as the basic techniques for the characterization of materials. Optical microscopy is expected to remain useful in the science world for a long time. Despite being presumed a basic tool, it is capable of giving very detailed information that reveals a lot about the materials preparations, heat treatment prior to observation, defects in the material as well as alloy composition. Relatively hard metals such as titanium, tungsten and steels are easy to prepare for microscopic examination unlike soft materials such as tin and aluminum that pose serious challenges during their preparation leading to defects such as deep scratch lines, embedded abrasive particles, dust particles, as well as water marks covering the polished surface. The material used in this study Cu50Ti25Zr15Ni10 was produced by arc melting. The alloy ingots were re-melted at least 4 times for homogenization of the master alloy. The alloy ingot was then suction cast into a 3mm rod. The alloy metals used for the ingots had purities greater than 99.9% and were purchased from Zhongnuo Advanced Materials (Beijing) Technology Co. Ltd China. The objective of this work was to show the importance of proper and correct specimen preparation in revealing the basic and detailed information concerning the structure, as well as its morphology. A perfectly ground and polished surface is free from defect arising from preparation method hence the presumption that microscopy is a basic science does since even advanced structures can be revealed. It is imperative that a good quality optical microscope be purchased especially when resources are scarce and advanced materials characterization techniques are not available. In can be concluded that with a good quality optical microscope, microscopy as a technique will continue to play a critical role during decision making and that a polished surface will only give accurate information about a given specimen if all preparation stages and steps are taken into consideration, adhered to and carefully and professionally done.

Investigation of the different particle size dust releases from rigid filter candles during pulse-jet cleaning

2021 ◽  
pp. 095440622110179
Author(s):  
Xin Luan ◽  
Zhongli Ji ◽  
Longfei Liu ◽  
Ruifeng Wang
Keyword(s):  
Particle Size ◽  
Critical Role ◽  
Operating Conditions ◽  
Solid Particles ◽  
Dust Particles ◽  
Cleaning Efficiency ◽  
Term Operation ◽  
Cleaning Performance ◽  
Experimental Apparatus ◽  
Pulse Jet

Rigid filters made of ceramic or metal are widely used to remove solid particles from hot gases at temperature above 260 °C in the petrochemical and coal industries. Pulse-jet cleaning of fine dust from rigid filter candles plays a critical role in the long-term operation of these filters. In this study, an experimental apparatus was fabricated to investigate the behavior of a 2050 mm filter candle, which included monitoring the variation of pressure dynamic characteristics over time and observing the release of dust layers that allowed an analysis of the cleaning performance of ISO 12103-1 test dusts with different particle size distributions. These results showed the release behavior of these dusts could be divided into five stages: radial expansion, axial crack, flaky release, irregular disruption and secondary deposition. The cleaning performance of smaller sized dust particles was less efficient as compared with larger sized dust particles under the same operating conditions primarily because large, flaky-shaped dust aggregates formed during the first three stages were easily broken into smaller, dispersed fragments during irregular disruption that forced more particles back to the filter surface during secondary deposition. Also, a “low-pressure and long-pulse width” cleaning method improved the cleaning efficiency of the A1 ultrafine test dust from 81.4% to 95.9%.

Tem Specimen Preparation by Mechanical Microthinning

1987 ◽  
Vol 115 ◽  
Author(s):  
H. K. Plummer ◽  
S. Shinozaki
Keyword(s):  
Soft Materials ◽  
Diamond Powder ◽  
Specimen Preparation ◽  
Ion Milling ◽  
Thin Specimen ◽  
Basic Premise ◽  
Mechanical Abrasion ◽  
Hard Materials ◽  
Transmission Electron ◽  
Lathe Tool

ABSTRACTMechanical abrasion has been used by the authors to prepare a variety of materials, mainly ceramics, which have been thinned to electron transparency. The basic premise of this technique is the rotation of a spherically shaped wood tool at right angles to a rotating 3mm specimen disk (∼100 μm thick). A slurry of 1/2 μm diamond powder in a glycerin vehicle thins the specimen and carries away the abraded matter. In addition to the wood tool other materials such as brass, teflon and polyethylene have been tried without success. Abrasion “marks” left on the thin specimen surface can be ignored in some situations or removed by a touch up ion milling at 3 keV for ∼1/2 hr. Recently, attempts to thin N+ implanted Al from the un-implanted side using a wood tool were found to be extremely time consuming, i.e. 60 hr or more. It was found that a spherical stainless steel tool produced a suitably thin transmission electron microscopy (TEM) specimen using glycerin as the vehicle and no diamond powder. Depending upon the pressure applied to the tool these specimens could be thinned in as little as 3 hr. The turning marks left by the lathe tool proved to be sufficient to thin the soft aluminum. From this result It appears that soft tools will thin hard materials and hard tools can be used to thin soft materials efficiently. A number of other specimens recently prepared using mechanical microthinning will also be presented.

Atomic Force Microscopy of Annealed Plain Carbon Steels

2015 ◽  
Author(s):  
Surendra Kumar Gupta ◽  
Patricia Iglesias Victoria
Keyword(s):  
Atomic Force Microscopy ◽  
Optical Microscopy ◽  
Interlamellar Spacing ◽  
Lamellar Spacing ◽  
Optical Microscope ◽  
Carbon Steels ◽  
Force Microscopy ◽  
Atomic Force

Microstructure of annealed plain carbon steels is examined using optical microscopy. When the inter-lamellar spacing in pearlite is small, optical microscope at 1000X is unable to resolve the ferrite and cementite lamellae. In hyper-eutectoid steels, cementite in pearlite appears as darker phase whereas the pro-eutectoid cementite appears as a lighter phase. Atomic force microscopy (AFM) of etched steels is able to resolve ferrite and cementite lamellae in pearlite at similar magnifications. Both cementite in pearlite as well as pro-eutectoid cementite appear as raised areas (hills) in AFM images. Interlamellar spacing in pearlite increases with increasing hardenability of steel.

scholarly journals Multimodal nonlinear optical microscopy reveals critical role of kinesin-1 in cartilage development

2017 ◽  
Vol 8 (3) ◽  
pp. 1771 ◽  
Author(s):  
Sicong He ◽  
Wenqian Xue ◽  
Zhigang Duan ◽  
Qiqi Sun ◽  
Xuesong Li ◽  
...  
Keyword(s):  
Optical Microscopy ◽  
Nonlinear Optical ◽  
Critical Role ◽  
Nonlinear Optical Microscopy ◽  
Cartilage Development

Development of a Combined Scanning Ion-Conductance and Nearfield Optical Microscope to Image Living Cells

1999 ◽  
Vol 5 (S2) ◽  
pp. 976-977
Author(s):  
M. Raval ◽  
D. Klenerman ◽  
T. Rayment ◽  
Y. Korchev ◽  
M. Lab
Keyword(s):  
Optical Microscopy ◽  
Biological Samples ◽  
Near Field ◽  
Sample Surface ◽  
Optical Microscope ◽  
Ion Conductance ◽  
Simultaneous Generation ◽  
Simple Arrangement ◽  
Wavelength Resolution ◽  
Sub Wavelength

It is important to be able to image biological samples in a manner that is non-invasive and allows the sample to retain its functionality during imaging.A member of the SPM (scanning probe microscopy) family, SNOM (scanning near-field optical microscopy), has emerged as a technique that allows optical and topographic imaging of biological samples whilst satisfying the above stated criteria. The basic operating principle of SNOM is as follows. Light is coupled down a fibre-optic probe with an output aperture of sub-wavelength dimensions. The probe is then scanned over the sample surface from a distance that is approximately equal to the size of its aperture. By this apparently simple arrangement, the diffraction limit posed by conventional optical microscopy is overcome and simultaneous generation of optical and topographic images of sub-wavelength resolution is made possible. Spatial resolution values of lOOnm in air and 60nm in liquid[1,2] are achievable with SNOM.

scholarly journals Progress in soil geography I: Reinvigoration

2019 ◽  
Vol 43 (6) ◽  
pp. 827-854 ◽  
Author(s):  
Bradley A Miller ◽  
Eric C Brevik ◽  
Paulo Pereira ◽  
Randall J Schaetzl
Keyword(s):  
Land Use Planning ◽  
Precision Agriculture ◽  
Critical Role ◽  
Soil Mapping ◽  
Digital Soil Mapping ◽  
Soil Science ◽  
Accurate Information ◽  
Soil Maps ◽  
Geospatial Technologies ◽  
Soil Geography

The geography of soil is more important today than ever before. Models of environmental systems and myriad direct field applications depend on accurate information about soil properties and their spatial distribution. Many of these applications play a critical role in managing and preparing for issues of food security, water supply, and climate change. The capability to deliver soil maps with the accuracy and resolution needed by land use planning, precision agriculture, as well as hydrologic and meteorologic models is, fortunately, on the horizon due to advances in the geospatial revolution. Digital soil mapping, which utilizes spatial statistics and data provided by modern geospatial technologies, has now become an established area of study for soil scientists. Over 100 articles on digital soil mapping were published in 2018. The first and second generations of soil mapping thrived from collaborations between Earth scientists and geographers. As we enter the dawn of the third generation of soil maps, those collaborations remain essential. To that end, we review the historical connections between soil science and geography, examine the recent disconnect between those disciplines, and draw attention to opportunities for the reinvigoration of the long-standing field of soil geography. Finally, we emphasize the importance of this reinvigoration to geographers.

scholarly journals ChipScope Symposium: Novel Approaches for a Chip-Sized Optical Microscope

Proceedings ◽  
2020 ◽  
Vol 56 (1) ◽  
pp. 5
Author(s):  
Angel Diéguez ◽  
Steffen Bornemann ◽  
Katarzyna Kluczyk-Korch ◽  
Kateryna Trofymchuk ◽  
Viktorija Glembockyte ◽  
...  
Keyword(s):  
Optical Microscopy ◽  
Light Emission ◽  
Optical Microscope ◽  
European Institutions ◽  
New Strategy ◽  
Novel Approaches ◽  
The Eu

In the Chipscope project funded by the EU, a completely new strategy towards optical microscopy is explored by a team of researchers from different European institutions. In this workshop, the different researchers of the project will explain the last advances obtained in the project, presenting the microscopes, how light emission is produced, and the detection principles and simulations.

Scanning acoustic microscopy of partly embedded cracks in polycrystalline alumina

1986 ◽  
Vol 320 (1554) ◽  
pp. 237-241 ◽  
Keyword(s):  
Optical Microscope ◽  
Acoustic Microscopy ◽  
Polished Surface ◽  
Scanning Acoustic Microscopy ◽  
Optimum Conditions ◽  
Frame Size ◽  
Polycrystalline Alumina ◽  
Microscope Images ◽  
Optical Micrographs ◽  
Scanning Electron

Reflection scanning acoustic microscopy (SAM) at 1 GHz has been used to examine artificially induced cracks in alumina samples. The results are compared with the corresponding optical micrographs and scanning electron microscope images. For a sample with a 0.08 μm centre-line average (CLA) surface finish, the SAM working with a 400 μm frame size, showed that a crack that appeared to be about 150 μm in length in the corresponding optical image was, in fact, at least 200 μm in length. For a sample with a good engineering finish of 0.15 μm CLA, the SAM was able to reveal crack detail to a degree comparable with that revealed by an optical microscope working under optimum conditions. On a sample with a highly polished surface it was possible to distinguish between cracks and grain boundaries by using the V (z) response of the SAM, in agreement with theory.

scholarly journals Monocytes Induce Reversible Focal Changes in Vascular Endothelial Cadherin Complex during Transendothelial Migration under Flow

2000 ◽  
Vol 148 (1) ◽  
pp. 203-216 ◽  
Author(s):  
Jennifer R. Allport ◽  
William A. Muller ◽  
Francis W. Luscinskas
Keyword(s):  
Endothelial Cell ◽  
Umbilical Vein ◽  
Critical Role ◽  
Vascular Endothelial Cell ◽  
Transendothelial Migration ◽  
Specimen Preparation ◽  
Vascular Endothelial ◽  
Leukocyte Transmigration ◽  
Static Conditions

The vascular endothelial cell cadherin complex (VE-cadherin, α-, β-, and γ-catenin, and p120/p100) localizes to adherens junctions surrounding vascular endothelial cells and may play a critical role in the transendothelial migration of circulating blood leukocytes. Previously, we have reported that neutrophil adhesion to human umbilical vein endothelial cell (HUVEC) monolayers, under static conditions, results in a dramatic loss of the VE-cadherin complex. Subsequent studies by us and others (Moll, T., E. Dejana, and D. Vestweber. 1998. J. Cell Biol. 140:403–407) suggested that this phenomenon might reflect degradation by neutrophil proteases released during specimen preparation. We postulated that some form of disruption of the VE-cadherin complex might, nonetheless, be a physiological process during leukocyte transmigration. In the present study, the findings demonstrate a specific, localized effect of migrating leukocytes on the VE-cadherin complex in cytokine-activated HUVEC monolayers. Monocytes and in vitro differentiated U937 cells induce focal loss in the staining of VE-cadherin, α-catenin, β-catenin, and plakoglobin during transendothelial migration under physiological flow conditions. These events are inhibited by antibodies that prevent transendothelial migration and are reversed following transmigration. Together, these data suggest that an endothelial-dependent step of transient and focal disruption of the VE-cadherin complex occurs during leukocyte transmigration.

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